Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds real behavioral context beyond that: how zones are derived (clustered swing highs/lows), what touch counts mean, and that results include nearest levels above/below with a distance metric.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.